Patents by Inventor Srinivas T. Reddy

Srinivas T. Reddy has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6577160
    Abstract: A programmable logic device has a plurality of super-regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of super-regions. Horizontal and vertical inter-super-region interconnection conductors are associated with each row and column, respectively. Each super-region includes a plurality of regions of programmable logic, and each region includes a plurality of subregions of programmable logic. Inter-region interconnection conductors are associated with each super-region. Local conductors are associated with each region. Shared driver circuits may be provided (e.g., for (1) receiving signals from the subregions and the horizontal and/or vertical conductors, and (2) applying selected received signals to the inter-region conductors, the horizontal and vertical conductors, and possibly also the local conductors).
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: June 10, 2003
    Assignee: Altera Corporation
    Inventors: Srinivas T. Reddy, Richard G. Cliff, Christopher F. Lane, Ketan H. Zaveri, Manuel M. Mejia, David Jefferson, Bruce B. Pedersen, Andy L. Lee
  • Publication number: 20030080778
    Abstract: A programmable logic device has a plurality of super-regions of programmable circuitry disposed on the device in a two-dimensional array of such super-regions. Each super-region includes a plurality of regions of programmable logic and a region of programmable memory. Each logic region includes a plurality of subregions of programmable logic. Each super-region has associated interconnection resources for allowing communication between the logic and memory regions of that super-region without the need to use, for such relatively local interconnections, the longer-length inter-super-region interconnection resources that are also provided on the device.
    Type: Application
    Filed: September 27, 2002
    Publication date: May 1, 2003
    Applicant: Altera Corporation
    Inventors: David E. Jefferson, Cameron McClintock, James Schleicher, Andy L. Lee, Manuel Mejia, Bruce B. Pedersen, Christopher F. Lane, Richard G. Cliff, Srinivas T. Reddy
  • Publication number: 20030076130
    Abstract: A programmable logic device has a plurality of super-regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of super-regions. Horizontal and vertical inter-super-region interconnection conductors are associated with each row and column, respectively. Each super-region includes a plurality of regions of programmable logic, and each region includes a plurality of subregions of programmable logic. Inter-region interconnection conductors are associated with each super-region, principally for bringing signals into the super-region and interconnecting the regions in the super-region. Local conductors are associated with each region, principally for bringing signals into the region. At the super-region level the device may be horizontally and vertically isomorphic, which helps make it possible to produce devices with low aspect ratios of one or nearly one. Shared driver circuits may be provided (e.g.
    Type: Application
    Filed: June 10, 2002
    Publication date: April 24, 2003
    Inventors: Srinivas T. Reddy, Richard G. Cliff, Christopher F. Lane, Ketan H. Zaveri, Manuel M. Mejia, David Jefferson, Bruce B. Pedersen, Andy L. Lee
  • Publication number: 20030033584
    Abstract: A programmable logic device is provided that contains circuitry that may be used for observing logic signals from programmable logic circuits on the device for testing the operation of the device. Circuitry is also provided that may be used for preloading data into various circuits on the device. The logic signal observing circuitry may allow registered signals to be observed, may allow combinatorial signals to be observed, or may allow both registered and combinatorial signals to be observed.
    Type: Application
    Filed: September 25, 2002
    Publication date: February 13, 2003
    Applicant: Altera Corporation
    Inventors: Ketan Zaveri, Christopher F. Lane, Srinivas T. Reddy, Andy L. Lee, Cameron R. McClintock, Bruce B. Pedersen
  • Publication number: 20030016053
    Abstract: A programmable logic array integrated circuit device includes a plurality of regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns. Interconnection conductors are associated with each row and column. The interconnection conductors associated with each row include some that extend continuously along the entire length of the row and some that extend continuously along only the left or right half of the row. To increase the flexibility with which the logic regions can be connected to the row and column conductors, adjacent regions are paired and circuitry is provided for allowing the outputs of each pair to be swapped for driving the row and column conductors. Registers in logic regions can still be used for other purposes when not being used to register the main combinatorial outputs of the logic regions. Many other enhanced features are also provided.
    Type: Application
    Filed: April 8, 2002
    Publication date: January 23, 2003
    Inventors: Richard G. Cliff, Srinivas T. Reddy, David Edward Jefferson, Rina Raman, L. Todd Cope, Christopher F. Lane, Joseph Huang, Francis B. Heile, Bruce B. Pedersen, David Wolk Mendel, Craig Schilling Lytle, Robert Richard Noel Bielby, Kerry Veenstra
  • Patent number: 6480028
    Abstract: A programmable logic device has a plurality of super-regions of programmable circuitry disposed on the device in a two-dimensional array of such super-regions. Each super-region includes a plurality of regions of programmable logic and a region of programmable memory. Each logic region includes a plurality of subregions of programmable logic. Each super-region has associated interconnection resources for allowing communication between the logic and memory regions of that super-region without the need to use, for such relatively local interconnections, the longer-length inter-super-region interconnection resources that are also provided on the device.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: November 12, 2002
    Assignee: Altera Corporation
    Inventors: David E. Jefferson, Cameron McClintock, James Schleicher, Andy L. Lee, Manuel Mejia, Bruce B. Pederson, Christopher F. Lane, Richard G. Cliff, Srinivas T. Reddy
  • Patent number: 6481000
    Abstract: A programmable logic device is provided that contains circuitry that may be used for observing logic signals from programmable logic circuits on the device for testing the operation of the device. Circuitry is also provided that may be used for preloading data into various circuits on the device. The logic signal observing circuitry may allow registered signals to be observed, may allow combinatorial signals to be observed, or may allow both registered and combinatorial signals to be observed.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: November 12, 2002
    Assignee: Altera Corporation
    Inventors: Ketan Zaveri, Christopher F. Lane, Srinivas T. Reddy, Andy L. Lee, Cameron R. McClintock, Bruce B. Pedersen
  • Publication number: 20020166106
    Abstract: An embodiment of this invention pertains to a wire that interconnects multiple function blocks within a programmable logic device (“PLD”). An electrically optimum physical length is determined for the wire. A wire having the electrically optimum physical length transmits a signal down the wire as fast as possible. Some of the wires used in the PLD have a physical length substantially the same as the electrically optimum physical length or an adjustment of the electrically optimum physical length to account for non-electrical considerations. The physical length, as used herein, is the measured length of the wire. A logical length of the wire, as used herein, is the number of function blocks that the wire spans. Given that the function blocks have a different height and width, the logical length of the wire varies depending on the orientation of the wire.
    Type: Application
    Filed: January 25, 2002
    Publication date: November 7, 2002
    Inventors: David M. Lewis, Vaughn Betz, Paul Leventis, Michael Chan, Cameron R. McClintock, Andy L. Lee, Christopher F. Lane, Srinivas T. Reddy, Richard Cliff
  • Patent number: 6467017
    Abstract: A programmable logic device has embedded random access memory (“RAM”) that can function equally well in either single-port or dual-port operation. The RAM is dual-port RAM whose read address inputs and write address inputs are both connected to a conductor bus via two different sparsely populated programmable interconnection resources. The programmable interconnection resources are arranged so that each pair of corresponding read address and write address inputs can be connected to at least one conductor in common on the conductor bus, allowing the RAM to be configured to mimic a single-port RAM as read address signals and write address signals originating at remote components of the programmable logic device “think” they are being directed to the same address inputs.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: October 15, 2002
    Assignee: Altera Corporation
    Inventors: Tony K. Ngai, Rakesh H. Patel, Srinivas T. Reddy, Richard G. Cliff
  • Patent number: 6462577
    Abstract: A programmable logic device is provided in which logic array blocks (LABs) may be programmably configured for use as one of a variety of memory structures. The configurable memory structures may have separate read and write addresses, thereby making it possible to implement a variety of memory structures such as FIFO memory, ROM, RAM, and shift-registers.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: October 8, 2002
    Assignee: Altera Corporation
    Inventors: Andy L. Lee, Christopher F. Lane, Srinivas T. Reddy, Brian D. Johnson, Ketan H. Zaveri, Mario Guzman, Quyen Doan
  • Patent number: 6417694
    Abstract: A programmable logic device has a plurality of super-regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of super-regions. Horizontal and vertical inter-super-region interconnection conductors are associated with each row and column, respectively. Each super-region includes a plurality of regions of programmable logic, and each region includes a plurality of subregions of programmable logic. Inter-region interconnection conductors are associated with each super-region, principally for bringing signals into the super-region and interconnecting the regions in the super-region. Local conductors are associated with each region, principally for bringing signals into the region. At the super-region level the device may be horizontally and vertically isomorphic, which helps make it possible to produce devices with low aspect ratios of one or nearly one. Shared driver circuits may be provided (e.g.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: July 9, 2002
    Assignee: Altera Corporation
    Inventors: Srinivas T. Reddy, Richard G. Cliff, Christopher F. Lane, Ketan H. Zaveri, Manuel M. Mejia, David Jefferson, Bruce B. Pedersen, Andy L. Lee
  • Publication number: 20020084801
    Abstract: A programmable logic device has a plurality of super-regions of programmable circuitry disposed on the device in a two-dimensional array of such super-regions. Each super-region includes a plurality of regions of programmable logic and a region of programmable memory. Each logic region includes a plurality of subregions of programmable logic. Each super-region has associated interconnection resources for allowing communication between the logic and memory regions of that super-region without the need to use, for such relatively local interconnections, the longer-length inter-super-region interconnection resources that are also provided on the device.
    Type: Application
    Filed: February 1, 2002
    Publication date: July 4, 2002
    Applicant: Altera Corporation
    Inventors: David E. Jefferson, Cameron McClintock, James Schleicher, Andy L. Lee, Manuel Mejia, Bruce B. Pedersen, Christopher F. Lane, Richard G. Cliff, Srinivas T. Reddy
  • Patent number: 6392438
    Abstract: A programmable logic array integrated circuit device includes a plurality of regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns. Interconnection conductors are associated with each row and column. The interconnection conductors associated with each row include some that extend continuously along the entire length of the row and some that extend continuously along only the left or right half of the row. To increase the flexibility with which the logic regions can be connected to the row and column conductors, adjacent regions are paired and circuitry is provided for allowing the outputs of each pair to be swapped for driving the row and column conductors. Registers in logic regions can still be used for other purposes when not being used to register the main combinatorial outputs of the logic regions. Many other enhanced features are also provided.
    Type: Grant
    Filed: October 6, 2000
    Date of Patent: May 21, 2002
    Assignee: Altera Corporation
    Inventors: Richard G. Cliff, Srinivas T. Reddy, David Edward Jefferson, Rina Raman, L. Todd Cope, Christopher F. Lane, Joseph Huang, Francis B. Heile, Bruce B. Pedersen, David Wolk Mendel, Craig Schilling Lytle, Robert Richard Noel Bielby, Kerry Veenstra
  • Patent number: 6392954
    Abstract: A dual-port programmable logic device memory array is provided. Selectable-size data words may be written to and read from the array concurrently. Data is written into the array using write column decoder and data selection logic. The size of the data words handled by the write column decoder and data selection logic is controlled by mode select signals. Data is read from the array using read column decoder and data selection logic. The size of the data words handled by the read column decoder and data selection logic is also controlled by mode select signals. The write column decoder and data selection logic may be used to write data into the memory array at one selected location at the same time that the read column decoder and data selection logic is used to read data from the array at another selected location. A write row address decoder and a read row address decoder are used to independently address individual rows of memory cells in the memory array during writing and reading, respectively.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: May 21, 2002
    Assignee: Altera Corporation
    Inventors: Srinivas T. Reddy, Christopher F. Lane, Manuel Mejia, Richard G. Cliff, Kerry Veenstra
  • Patent number: 6384630
    Abstract: Programmable logic array devices are programmed from programming devices in networks that facilitate programming any number of such logic devices with programs of any size or complexity. The source of programming data and control may be a microprocessor or one or more serial EPROMs, one EPROM being equipped with a clock circuit. Several parallel data streams may be used to speed up the programming operation. A clock circuit with a programmably variable speed may be provided to facilitate programming logic devices with different speed characteristics. The programming protocol may include an acknowledgment from the logic device(s) to the programming data source after each programming data transmission so that the source can automatically transmit programming data at the speed at which the logic device is able to accept that data.
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: May 7, 2002
    Assignee: Altera Corporation
    Inventors: Richard G. Cliff, Srinivas T. Reddy, Kerry Veenstra, Andreas Papaliolios, Chiakang Sung, Richard Shaw Terrill, Rina Raman, Robert Richard Noel Bielby
  • Patent number: 6373280
    Abstract: A programmable logic integrated circuit device has a plurality of areas of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of such areas. A so-called “fast conductor” network is provided on the device for rapidly and efficiently distributing a relatively small number of signals to substantially any logic area on the device. The fast conductor network has several main conductors that substantially bisect the array in one direction (e.g., by extending parallel to the column axis). Some main conductors can carry signals from off the device. Other main conductors can carry signals generated on the device. The network further includes secondary conductors that extend transverse to the main conductors (e.g., along each row of logic areas). Programmable logic connectors are provided for selectively applying signals from the main conductors to the secondary conductors and from the secondary conductors to the logic areas.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: April 16, 2002
    Assignee: Altera Corporation
    Inventors: Christopher F. Lane, Srinivas T. Reddy
  • Publication number: 20020041191
    Abstract: A programmable logic device has a plurality of super-regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of super-regions. Horizontal and vertical inter-super-region interconnection conductors are associated with each row and column, respectively. Each super-region includes a plurality of regions of programmable logic, and each region includes a plurality of subregions of programmable logic. Inter-region interconnection conductors are associated with each super-region, principally for bringing signals into the super-region and interconnecting the regions in the super-region. Local conductors are associated with each region, principally for bringing signals into the region. At the super-region level the device may be horizontally and vertically isomorphic, which helps make it possible to produce devices with low aspect ratios of one or nearly one. Shared driver circuits may be provided (e.g.
    Type: Application
    Filed: September 19, 2001
    Publication date: April 11, 2002
    Applicant: Altera Corporation
    Inventors: Srinivas T. Reddy, Richard G. Cliff, Christopher F. Lane, Ketan H. Zaveri, Manuel M. Mejia, David Jefferson, Bruce B. Pedersen, Andy L. Lee
  • Patent number: 6366121
    Abstract: A programmable logic array integrated circuit device has a plurality of regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns of regions. The output signals of several regions share a group of drivers for applying region output signals to interconnection conductors that convey signals between regions. This conserves driver resources and increases signal routing flexibility. Various approaches can be used for configuring the interconnection conductors to also conserve interconnection conductor resources. Logic regions may be used to directly drive specific input/output cells, thereby simplifying signal routing to the I/O cells and also possibly simplifying the structure of the I/O cells (e.g., by allowing certain I/O cell functions to be performed in the associated logic region).
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: April 2, 2002
    Assignee: Altera Corporation
    Inventors: Richard G. Cliff, Francis B. Heile, Joseph Huang, Christopher F. Lane, Fung Fung Lee, Cameron McClintock, David W. Mendel, Ninh D. Ngo, Bruce B. Pedersen, Srinivas T. Reddy, Chiakang Sung, Kerry Veenstra, Bonnie I. Wang
  • Patent number: 6356110
    Abstract: A logic array block (LAB) that is programmably selectively configurable for use as a multifunction memory array is provided. The LAB is configurable for operation in at least two modes: in a first mode, each logic element within the LAB is individually configurable to perform logic functions; in a second mode, the logic elements are collectively usable as a multifunction memory array. The multifunction memory array may be addressed on a LAB-wide basis with separate read and write addresses, such that it may be configured to implement a variety of memory schemes, including first-in-first-out (FIFO) memory and random access memory (RAM).
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: March 12, 2002
    Assignee: Altera Corporation San Jose CA
    Inventors: Srinivas T. Reddy, Brian D. Johnson, Christopher F. Lane, Ketan H. Zaveri
  • Patent number: 6351152
    Abstract: A look-up table circuit implemented with MOS transistors that uses combinational logic to generate signals that enable the transistors. A circuit using 16 inputs and 4 select lines is disclosed. Two of the select lines are used as inputs to combinational logic including four NOR gates to generate enable signals for transistors in a third stage of the circuit. This produces a reduction in the propagation delay of a signal from the input to the output of the look-up table circuit.
    Type: Grant
    Filed: September 23, 1999
    Date of Patent: February 26, 2002
    Assignee: Altera Corporation
    Inventors: Srinivas T. Reddy, Anil Gupta